On the one hand, the invention relates to a method for weaving a fabric comprising:                a backing fabric formed by backing warp yarns, comprising binding warp yarns, and first and second weft yarns;        one or several tension warp yarns;        non-pattern forming and/or pattern forming pile warp yarns, pattern forming pile burls being formed by the pattern forming pile warp yarns, and each pattern forming pile burl being interlaced round at least one third weft yarn situated at the back of the fabric with respect to the tension warp yarns.        
On the other hand, the invention relates to a fabric comprising:                a backing fabric, formed by backing warp yarns, comprising binding warp yarns and first and second weft yarns;        one or several tension warp yarns;        non-pattern forming and/or pattern forming pile warp yarns, the pattern forming pile warp yarns being provided to form pattern forming pile burls, and each pattern forming pile burl being interlaced round at least one third weft yarn which is situated at the back of the fabric with respect to the tension warp yarns.        
Hand-knotted fabrics, for instance, carpets are characterized by:                a high density;        a fine design;        a perfect back, showing no warp yarns.        
To produce a hand-knotted fabric a multitude of warp yarns are vertically arranged next to one another between a warp beam to supply the warp yarns and a cloth beam for winding the knotted cloth. Between the two, warp yarns are tightened.
When hand-knotting, the knotter is knotting horizontally pile yarns round the warp yarns, usually the knot being interlaced round two adjacent warp yarns (as represented in “Die Teppichindustrie”, Hans Oswald, 1965, Meliand Textilberichte, Heidelberg, pages 174 and 175). When horizontally a complete row of knots is made, one or several wefts are inserted between the warp yarns and, by means of a reed, the weft(s) is (are) beaten up against the knots, which in turn are beaten up against the fabric already formed. Then the knotter may make another row of knots and repeat the process.
From the figures can be deduced that the warp yarns are completely surrounded by the knotted pile yarn, which means that they will cover the warp yarns at the back. When the row of knots is well beaten up, which is required in order to obtain a high quality knotted fabric having a good pile anchorage, no backing warp yarns may appear at the back of the fabric, because of which the pattern of the fabric is perfect, also at the back. It is possible to produce hand-knotted fabrics, such as carpets, having high densities and a very clear pattern. Hand-knotting, however, is a very labour intensive production method.
Weaving itself, and more particular face-to-face weaving is a far more productive production method. However, with these weaving techniques, the pile warp yarn is interlaced round weft yarns, which at best are extending at the back of the fabric with respect to a tension warp yarn and a large part of the backing warp yarns are running visibly at the back of the fabric, because they interlace the weft yarns in the backing fabric, also those at the back of the fabric. The back of such fabrics therefore has a completely different aspect than the back of a knotted carpet.